The present invention relates to a connector, and more particularly, to a connector having signal contacts that transmit/receive signals to/from a counter connector, and non-signal contacts adapted for non-signal purposes such as power supply, and ground connection.
In general, in a connector adapted to transmit/receive signals and power supply to/from external apparatuses, a plurality of contacts including signal contacts for signal transmission, and non-signal contacts to be used for non-signal purposes such as power supply and ground connection, are arranged in one or more arrays. In such cases, in order to suppress cross-talk in signals transmitted at high-speed through the signal contacts, an arranging scheme is employed, for example, in which a non-signal contact is inserted between one signal contact and other signal contact so that the space between the signal contacts can be widened.
However, in recent years, with a decrease in size and an increase in density of electronic devices such as portable devices and information devices, connectors are also required to reduce in size and thus the space between two adjacent contacts in a connector is decreased as well. Therefore it becomes difficult to satisfactorily suppress cross-talk, only by widening the space between the signal contacts in a certain limited range.
For example, JP 2008-41656 A discloses a connector in which contacts are arranged in two rows of an upper row and a lower row. As shown in FIG. 28, in the lower row, a ground contact 2 is disposed adjacent to two signal contacts 1 that constitute a differential signal contact pair, and as shown in FIG. 29, a ground plate 4 extending in a connector fitting direction is disposed between the signal contacts 1 and the ground contact 2 in the lower row and signal contacts 3 in the upper row. In this way, the circumference of the differential signal contact pair is encompassed by the ground contact 2 and the ground plate 4 so as to improve cross-talk suppression.
However, for example, in a connector in which the contact arranging pitch is reduced to about 0.5 mm or less, and a high speed transmission of 5 Gbps (gigabits per second) or more is enabled, there is a problem in which cross-talk is not satisfactorily suppressed even if the circumference of signal contacts is encompassed by a ground contact and a ground plate.